A collecting device for the brake dust that is produced in the motor vehicle wheel brake by abrasion of the brake pads when braking a motor vehicle is disclosed in German patent application 196 43 869 C2. The brake dust collecting device is designed as a suction device that includes a dust collector whose end facing the brake disc has a suction opening and whose other end is connected by a suction line to the collecting container for collecting the brake dust. The collecting container is connected by a suction line to the intake manifold of the combustion engine so that the vacuum present in the intake manifold is also acting in the collecting container and in this way removal by suction of the brake dust and collection in the collecting container can be realized.
This configuration requires a flow connection between the intake manifold of the induction tract of the internal combustion engine and the collecting container for the brake dust; this requires a significant constructive expenditure. A disadvantage is also to be seen in that by branching off the suction line into the collecting container the pressure in the induction tract is affected so that also the air supply into the cylinders of the internal combustion engine changes. This must be taken into consideration in the motor control. Moreover, a use in charged internal combustion engines is not possible because of the overpressure produced by the compressor.
It is therefore an object of the present invention to provide with simple constructive means an effective brake dust collecting device for motor vehicles. Advantageously, the brake dust collecting device should also have high efficiency.